I haven’t seen any phone offered by these manufacturers that is as small as iPhone 13 mini. At best they’re just marginally smaller than iPhone 15.
There is no good alternative anymore if you’re looking for a truly small phone.
The options on Android aren’t much better, unless you go for some obscure manufacturer who won’t support the phone with updates 1 year after its life cycle.
Apple was for a while the only remaining flagship manufacturer who actually provided mini models. Ironic, because Android is supposed to be the alternative providing more options.
I’m talking about small phones. iPhone 13 mini was the last decent option when it came to small phones. Neither Google or Samsung make phones that small. The smallest phones they make are same size as a regular iPhone 13.
Now there’s only a few “obscure” manufacturers left who make small phones. “Obscure” manufacturers usually lack long term support on both the software and the hardware side to be a decent option.